I've used Dupli-Color Rust Fix quite a bit, if I remember correctly the instructions say wait 24 hours then paint over it. Mainly I use this for smaller parts or parts that the rust can't be easily removed by grit blasting, etc. Have not had any issue with the paint when topcoating over Rust Fix.
I have not used it, but you can also top coat over Eastwood's Rust Encapsulator: https://www.eastwood.com/eastwood-rust-encapsulator-black-aerosol-15-ounce.html?SRCCODE=PLA00010&gclid=Cj0KCQjwz6PnBRCPARIsANOtCw37qP0S7yfm3p8SdnhI9AmWqwFAnF6qYwWXd1nwryQ0JRI-gSr3O9saAheLEALw_wcB